Rock Springs Capital Management 13F-HR Quarterly holdings report by institutional manager

The Securities and Exchange Commission has not necessarily reviewed the information in this filing and has not determined if it is accurate and complete.
The reader should not assume that the information is accurate and complete.

UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549
FORM 13F

FORM 13F INFORMATION TABLE

OMB APPROVAL

OMB Number:		3235-0006
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COLUMN 1	COLUMN 2	COLUMN 3	COLUMN 4	COLUMN 5			COLUMN 6	COLUMN 7	COLUMN 8
			VALUE	SHRS OR	SH/	PUT/	INVESTMENT	OTHER	VOTING AUTHORITY
NAME OF ISSUER	TITLE OF CLASS	CUSIP	(x$1000)	PRN AMT	PRN	CALL	DISCRETION	MANAGER	SOLE	SHARED	NONE
ABBVIE INC	COM	00287Y109	10,908	150,000	SH		SOLE		150,000	0	0
ACADIA HEALTHCARE COMPANY IN	COM	00404A109	36,872	1,055,000	SH		SOLE		1,055,000	0	0
ACHILLION PHARMACEUTICALS IN	COM	00448Q201	7,906	2,950,000	SH		SOLE		2,950,000	0	0
ACLARIS THERAPEUTICS INC	COM	00461U105	4,441	2,028,000	SH		SOLE		2,028,000	0	0
ADAPTIMMUNE THERAPEUTICS PLC	SPONDS ADR	00653A107	3,518	875,000	SH		SOLE		875,000	0	0
ADAPTIVE BIOTECHNOLOGIES COR	COM	00650F109	28,980	600,000	SH		SOLE		600,000	0	0
AEGLEA BIOTHERAPEUTICS INC	COM	00773J103	5,480	800,000	SH		SOLE		800,000	0	0
AGILENT TECHNOLOGIES INC	COM	00846U101	13,650	182,800	SH		SOLE		182,800	0	0
AGIOS PHARMACEUTICALS INC	COM	00847X104	8,505	170,500	SH		SOLE		170,500	0	0
AKERO THERAPEUTICS INC	COM	00973Y108	4,309	225,000	SH		SOLE		225,000	0	0
ALDER BIOPHARMACEUTICALS INC	COM	014339105	18,388	1,562,300	SH		SOLE		1,562,300	0	0
ALDER BIOPHARMACEUTICALS INC	NOTE 2.500% 2/0	014339AA3	4,672	5,000,000	PRN		SOLE		5,000,000	0	0
ALEXION PHARMACEUTICALS INC	COM	015351109	31,763	242,500	SH		SOLE		242,500	0	0
ALIGN TECHNOLOGY INC	COM	016255101	28,739	105,000	SH		SOLE		105,000	0	0
ALLAKOS INC	COM	01671P100	17,505	404,000	SH		SOLE		404,000	0	0
ALNYLAM PHARMACEUTICALS INC	COM	02043Q107	23,778	327,700	SH		SOLE		327,700	0	0
AMARIN CORP PLC	SPONS ADR NEW	023111206	87,740	4,525,000	SH		SOLE		4,525,000	0	0
AMICUS THERAPEUTICS INC	COM	03152W109	12,480	1,000,000	SH		SOLE		1,000,000	0	0
ANAPTYSBIO INC	COM	032724106	12,328	218,500	SH		SOLE		218,500	0	0
ANTHEM INC	COM	036752103	5,644	20,000	SH		SOLE		20,000	0	0
ARDELYX INC	COM	039697107	5,380	2,000,000	SH		SOLE		2,000,000	0	0
ARGENX SE	SPONSORED ADR	04016X101	25,725	181,700	SH		SOLE		181,700	0	0
ARVINAS INC	COM	04335A105	3,299	150,000	SH		SOLE		150,000	0	0
ASCENDIS PHARMA A S	SPONSORED ADR	04351P101	24,585	213,500	SH		SOLE		213,500	0	0
ASSEMBLY BIOSCIENCES INC	COM	045396108	7,554	560,000	SH		SOLE		560,000	0	0
AUDENTES THERAPEUTICS INC	COM	05070R104	15,523	410,000	SH		SOLE		410,000	0	0
AXOGEN INC	COM	05463X106	11,959	603,970	SH		SOLE		603,970	0	0
AXONICS MODULATION TECH INC	COM	05465P101	16,388	400,000	SH		SOLE		400,000	0	0
BAXTER INTL INC	COM	071813109	24,627	300,700	SH		SOLE		300,700	0	0
BEIGENE LTD	SPONSORED ADR	07725L102	26,624	214,800	SH		SOLE		214,800	0	0
BIOGEN INC	COM	09062X103	22,802	97,500	SH	Call	SOLE		97,500	0	0
BIOHAVEN PHARMACTL HLDG CO L	COM	G11196105	15,042	343,500	SH		SOLE		343,500	0	0
BIOMARIN PHARMACEUTICAL INC	COM	09061G101	12,205	142,500	SH		SOLE		142,500	0	0
BLUEBIRD BIO INC	COM	09609G100	5,978	47,000	SH		SOLE		47,000	0	0
BLUEPRINT MEDICINES CORP	COM	09627Y109	29,006	307,500	SH		SOLE		307,500	0	0
BOSTON SCIENTIFIC CORP	COM	101137107	41,691	970,000	SH		SOLE		970,000	0	0
BRISTOL MYERS SQUIBB CO	COM	110122108	47,618	1,050,000	SH		SOLE		1,050,000	0	0
CELGENE CORP	COM	151020104	17,115	185,150	SH		SOLE		185,150	0	0
CHIASMA INC	COM	16706W102	4,856	650,000	SH		SOLE		650,000	0	0
CIGNA CORP NEW	COM	125523100	28,721	182,300	SH		SOLE		182,300	0	0
CLOVIS ONCOLOGY INC	COM	189464100	3,807	256,000	SH		SOLE		256,000	0	0
COHERUS BIOSCIENCES INC	COM	19249H103	41,548	1,880,000	SH		SOLE		1,880,000	0	0
COLLEGIUM PHARMACEUTICAL INC	COM	19459J104	20,749	1,577,893	SH		SOLE		1,577,893	0	0
COMPUGEN LTD	ORD	M25722105	4,224	1,100,000	SH		SOLE		1,100,000	0	0
CORREVIO PHARMA CORP	COM	22026V105	2,592	1,200,000	SH		SOLE		1,200,000	0	0
CORVUS PHARMACEUTICALS INC	COM	221015100	1,496	400,000	SH		SOLE		400,000	0	0
COVETRUS INC	COM	22304C100	788	32,231	SH		SOLE		32,231	0	0
CYMABAY THERAPEUTICS INC	COM	23257D103	6,444	900,000	SH		SOLE		900,000	0	0
DERMIRA INC	COM	24983L104	7,409	775,000	SH		SOLE		775,000	0	0
DERMIRA INC	NOTE 3.000% 5/1	24983LAB0	865	1,000,000	PRN		SOLE		1,000,000	0	0
DYNAVAX TECHNOLOGIES CORP	COM NEW	268158201	2,594	650,000	SH		SOLE		650,000	0	0
EDWARDS LIFESCIENCES CORP	COM	28176E108	33,900	183,500	SH		SOLE		183,500	0	0
ENCOMPASS HEALTH CORP	COM	29261A100	51,005	805,000	SH		SOLE		805,000	0	0
EPIZYME INC	COM	29428V104	23,219	1,850,100	SH		SOLE		1,850,100	0	0
EXACT SCIENCES CORP	COM	30063P105	46,862	397,000	SH		SOLE		397,000	0	0
FIBROGEN INC	COM	31572Q808	13,825	306,000	SH		SOLE		306,000	0	0
FIVE PRIME THERAPEUTICS INC	COM	33830X104	3,172	526,100	SH		SOLE		526,100	0	0
FRESHPET INC	COM	358039105	10,695	235,000	SH		SOLE		235,000	0	0
GALAPAGOS NV	SPON ADR	36315X101	21,273	165,000	SH		SOLE		165,000	0	0
GAMIDA CELL LTD	SHS	M47364100	5,080	1,000,000	SH		SOLE		1,000,000	0	0
GLOBAL BLOOD THERAPEUTICS IN	COM	37890U108	13,939	265,000	SH		SOLE		265,000	0	0
GLOBAL CORD BLOOD CORPORATIO	SHS	G39342103	5,347	925,000	SH		SOLE		925,000	0	0
GUARDANT HEALTH INC	COM	40131M109	16,403	190,000	SH		SOLE		190,000	0	0
GW PHARMACEUTICALS PLC	ADS	36197T103	104,296	605,000	SH		SOLE		605,000	0	0
HCA HEALTHCARE INC	COM	40412C101	61,502	455,000	SH		SOLE		455,000	0	0
HERON THERAPEUTICS INC	COM	427746102	558	30,000	SH		SOLE		30,000	0	0
HOMOLOGY MEDICINES INC	COM	438083107	8,317	425,000	SH		SOLE		425,000	0	0
IDEXX LABS INC	COM	45168D104	33,095	120,200	SH		SOLE		120,200	0	0
IMMUNOMEDICS INC	COM	452907108	12,414	895,000	SH		SOLE		895,000	0	0
INCYTE CORP	COM	45337C102	26,533	312,300	SH		SOLE		312,300	0	0
INSMED INC	COM PAR $.01	457669307	22,784	890,000	SH		SOLE		890,000	0	0
INSMED INC	NOTE 1.750% 1/1	457669AA7	5,849	6,000,000	PRN		SOLE		6,000,000	0	0
INSULET CORP	COM	45784P101	29,188	244,500	SH		SOLE		244,500	0	0
INTERCEPT PHARMACEUTICALS IN	COM	45845P108	3,979	50,000	SH		SOLE		50,000	0	0
INTERSECT ENT INC	COM	46071F103	17,980	790,000	SH		SOLE		790,000	0	0
INTUITIVE SURGICAL INC	COM NEW	46120E602	79,994	152,500	SH		SOLE		152,500	0	0
INVITAE CORP	COM	46185L103	26,438	1,125,000	SH		SOLE		1,125,000	0	0
IRHYTHM TECHNOLOGIES INC	COM	450056106	39,510	499,615	SH		SOLE		499,615	0	0
KALEIDO BIOSCIENCES INC	COM	483347100	1,161	100,050	SH		SOLE		100,050	0	0
KARUNA THERAPEUTICS INC	COM	48576A100	8,278	413,500	SH		SOLE		413,500	0	0
LA JOLLA PHARMACEUTICAL CO	COM PAR $.0001 2	503459604	3,931	425,000	SH		SOLE		425,000	0	0
MACROGENICS INC	COM	556099109	5,091	300,000	SH		SOLE		300,000	0	0
MADRIGAL PHARMACEUTICALS INC	COM	558868105	26,926	256,900	SH		SOLE		256,900	0	0
MEDICINES CO	COM	584688105	29,176	800,000	SH		SOLE		800,000	0	0
MEDICINES CO	NOTE 2.500% 1/1	584688AE5	3,618	3,000,000	PRN		SOLE		3,000,000	0	0
MEDICINES CO	NOTE 2.750% 7/1	584688AG0	5,026	5,000,000	PRN		SOLE		5,000,000	0	0
MERSANA THERAPEUTICS INC	COM	59045L106	5,670	1,400,000	SH		SOLE		1,400,000	0	0
MIRATI THERAPEUTICS INC	COM	60468T105	20,858	202,500	SH		SOLE		202,500	0	0
MOLINA HEALTHCARE INC	COM	60855R100	29,487	206,000	SH		SOLE		206,000	0	0
MOMENTA PHARMACEUTICALS INC	COM	60877T100	4,980	400,000	SH		SOLE		400,000	0	0
MYOVANT SCIENCES LTD	COM	G637AM102	4,073	450,000	SH		SOLE		450,000	0	0
NABRIVA THERAPEUTICS PLC	SHS	G63637105	3,888	1,600,000	SH		SOLE		1,600,000	0	0
NEUROCRINE BIOSCIENCES INC	COM	64125C109	86,372	1,023,000	SH		SOLE		1,023,000	0	0
NEUROCRINE BIOSCIENCES INC	NOTE 2.250% 5/1	64125CAD1	1,317	1,000,000	PRN		SOLE		1,000,000	0	0
NEVRO CORP	COM	64157F103	12,674	195,500	SH		SOLE		195,500	0	0
NGM BIOPHARMACEUTICALS INC	COM	62921N105	5,140	351,100	SH		SOLE		351,100	0	0
NOVAVAX INC	COM NEW	670002401	952	162,500	SH		SOLE		162,500	0	0
NOVOCURE LTD	ORD SHS	G6674U108	12,330	195,000	SH		SOLE		195,000	0	0
OBSEVA SA	COM	H5861P103	12,667	1,120,000	SH		SOLE		1,120,000	0	0
ODONATE THERAPEUTICS INC	COM	676079106	15,777	430,000	SH		SOLE		430,000	0	0
PACIRA BIOSCIENCES	COM	695127100	54,363	1,250,000	SH		SOLE		1,250,000	0	0
PACIRA BIOSCIENCES	NOTE 2.375% 4/0	695127AD2	1,026	1,000,000	PRN		SOLE		1,000,000	0	0
PARATEK PHARMACEUTICALS INC	COM	699374302	1,796	450,000	SH		SOLE		450,000	0	0
PENUMBRA INC	COM	70975L107	38,240	239,000	SH		SOLE		239,000	0	0
PHASEBIO PHARMACEUTICALS INC	COM	717224109	18,673	1,423,256	SH		SOLE		1,423,256	0	0
PORTOLA PHARMACEUTICALS INC	COM	737010108	27,347	1,008,000	SH		SOLE		1,008,000	0	0
PRA HEALTH SCIENCES INC	COM	69354M108	23,796	240,000	SH		SOLE		240,000	0	0
PROTEOSTASIS THERAPEUTICS IN	COM	74373B109	390	400,000	SH		SOLE		400,000	0	0
PUMA BIOTECHNOLOGY INC	COM	74587V107	6,792	534,400	SH		SOLE		534,400	0	0
RA PHARMACEUTICALS INC	COM	74933V108	24,176	804,000	SH		SOLE		804,000	0	0
RADIUS HEALTH INC	COM NEW	750469207	30,450	1,250,000	SH		SOLE		1,250,000	0	0
RADIUS HEALTH INC	NOTE 3.000% 9/0	750469AA6	1,361	1,500,000	PRN		SOLE		1,500,000	0	0
RESTORBIO INC	COM	76133L103	4,080	400,000	SH		SOLE		400,000	0	0
RETROPHIN INC	COM	761299106	19,086	950,000	SH		SOLE		950,000	0	0
RHYTHM PHARMACEUTICALS INC	COM	76243J105	5,170	235,000	SH		SOLE		235,000	0	0
RIGEL PHARMACEUTICALS INC	COM NEW	766559603	10,962	4,200,000	SH		SOLE		4,200,000	0	0
RTI SURGICAL HOLDINGS INC	COM	74975N105	8,288	1,950,000	SH		SOLE		1,950,000	0	0
SAGE THERAPEUTICS INC	COM	78667J108	16,936	92,500	SH		SOLE		92,500	0	0
SAREPTA THERAPEUTICS INC	COM	803607100	49,384	325,000	SH		SOLE		325,000	0	0
SEATTLE GENETICS INC	COM	812578102	16,749	242,000	SH		SOLE		242,000	0	0
SPARK THERAPEUTICS INC	COM	84652J103	51,740	505,371	SH		SOLE		505,371	0	0
SPERO THERAPEUTICS INC	COM	84833T103	6,043	525,000	SH		SOLE		525,000	0	0
STRYKER CORP	COM	863667101	36,799	179,000	SH		SOLE		179,000	0	0
TELEFLEX INC	COM	879369106	43,050	130,000	SH		SOLE		130,000	0	0
THERAVANCE BIOPHARMA INC	COM	G8807B106	8,982	550,000	SH		SOLE		550,000	0	0
THERAVANCE BIOPHARMA INC	NOTE 3.250%11/0	88339KAA0	1,290	1,500,000	PRN		SOLE		1,500,000	0	0
THERMO FISHER SCIENTIFIC INC	COM	883556102	23,788	81,000	SH		SOLE		81,000	0	0
TRANSLATE BIO INC	COM	89374L104	12,746	1,009,179	SH		SOLE		1,009,179	0	0
ULTRAGENYX PHARMACEUTICAL IN	COM	90400D108	36,830	580,000	SH		SOLE		580,000	0	0
UNITEDHEALTH GROUP INC	COM	91324P102	144,210	591,000	SH		SOLE		591,000	0	0
VERTEX PHARMACEUTICALS INC	COM	92532F100	37,226	203,000	SH		SOLE		203,000	0	0
WELLCARE HEALTH PLANS INC	COM	94946T106	91,365	320,500	SH		SOLE		320,500	0	0
WEST PHARMACEUTICAL SVSC INC	COM	955306105	17,208	137,500	SH		SOLE		137,500	0	0
ZAI LAB LTD	ADR	98887Q104	19,179	550,000	SH		SOLE		550,000	0	0
ZOGENIX INC	COM NEW	98978L204	11,228	235,000	SH		SOLE		235,000	0	0